Rust 1.100 will stop shipping host tools for 32-bit Windows targets
The Compiler team is moving two i686 Windows targets to std-only, so 32-bit Windows builds will need cross-compiling from a supported host.
With Rust 1.100.0, the i686-pc-windows-msvc target drops from Tier 1 with host tools to Tier 1 without host tools, and i686-pc-windows-gnu drops from Tier 2 with host tools to Tier 2 without host tools. Prebuilt standard library builds will still be distributed for both.
The Compiler team gives practical reasons. Machines that only run 32-bit x86 Windows have not been sold for over 15 years, and the team has seen compiler binaries crash when built for the i686 MSVC target and GNU C++ builds run out of memory during the LLVM build.
After Rust 1.100, toolchains can no longer be installed on 32-bit Windows hosts. Developers who still ship 32-bit Windows binaries should plan to cross-compile from a supported host, such as a 64-bit Windows toolchain. Other 32-bit platforms are not affected, and the i686-pc-windows-msvc target will still be tested in CI.
Sources
Verified Oct 26, 2026 (official source). rustcompilerwindows